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Related papers: Explicit Pseudo-K\"ahler Metrics on Flag Manifolds

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This paper is devoted to the construction of a hyperkaehler structure on the complexification of any Hermitian-symmetric affine coadjoint orbit O of a semi-simple L*-group of compact type, which is compatible with the complex symplectic…

Mathematical Physics · Physics 2008-07-15 Alice Barbara Tumpach

We present an inductive strategy to show the existence of rational curves on compact Kaehler manifolds which are not minimal models but have a pseudoeffective canonical bundle. The tool for this inductive strategy is a weak subadjunction…

Algebraic Geometry · Mathematics 2017-10-26 Junyan Cao , Andreas Höring

We extend Tsuji's iterative construction of complete K\"ahler--Einstein metrics with negative scalar curvature to noncompact K\"ahler manifolds with bounded geometry, using Berndtsson's method from the compact setting. Consequently, given a…

Differential Geometry · Mathematics 2026-01-13 Quang-Tuan Dang , Tat Dat Tô

We discuss a technique to construct Ricci-flat hermitian metrics on complements of (some) anticanonical divisors of almost homogeneous manifolds and discuss when this metric is complete and K\"ahler. This construction has a strong interplay…

Differential Geometry · Mathematics 2007-05-23 Bert Koehler , Marco Kuehnel

We consider compact homogeneous spaces G/H of positive Euler characteristic endowed with an invariant almost complex structure J and the canonical action \theta of the maximal torus T ^{k} on G/H. We obtain explicit formula for the…

Algebraic Topology · Mathematics 2007-09-03 Victor M. Buchstaber , Svjetlana Terzic

We study the representation theory of the nested instantons quiver presented in [1], which describes a particular class of surface defects in four-dimensional supersymmetric gauge theories. We show that the moduli space of its stable…

Algebraic Geometry · Mathematics 2024-11-20 Giulio Bonelli , Nadir Fasola , Alessandro Tanzini

We study geometry, topology and deformation spaces of noncompact complex hyperbolic manifolds (geometrically finite, with variable negative curvature), whose properties make them surprisingly different from real hyperbolic manifolds with…

Differential Geometry · Mathematics 2015-06-26 Boris Apanasov

We consider compact K\"ahler manifolds acted on by a connected compact Lie group $K$ of isometries in Hamiltonian fashion. We prove that the squared moment map $\|\mu\|^2$ is constant if and only if the manifold is biholomorphically and…

Symplectic Geometry · Mathematics 2007-05-23 Anna Gori , Fabio Podesta'

For $U(2)$-invariant 4-metrics, we show that the $B^t$-flat metrics are very different from the other canonical metrics (Bach-flat, Einstein, extremal K\"ahler, etc). We show every $U(2)$-invariant metric is conformal to two separate…

Differential Geometry · Mathematics 2023-09-04 Keaton Naff , Brian Weber

We prove a universal embedding theorem for flag manifolds: every flag manifold admits a holomorphic isometric embedding into an irreducible classical flag manifold. This result generalizes the classical celebrated embedding theorems of…

Differential Geometry · Mathematics 2025-08-01 Andrea Loi , Roberto Mossa , Fabio Zuddas

We show that irreducible unitary representations of nilpotent super Lie groups can be obtained by induction from a distinguished class of sub super Lie groups. These sub super Lie groups are natural analogues of polarizing subgroups that…

Representation Theory · Mathematics 2015-05-13 Hadi Salmasian

Half Lie groups exist only in infinite dimensions: They are smooth manifolds and topological groups such that right translations are smooth, but left translations are merely required to be continuous. The main examples are groups of $H^s$…

Differential Geometry · Mathematics 2025-01-08 Martin Bauer , Philipp Harms , Peter W. Michor

Let $(M^n, g)$ be a compact K\"ahler manifold with nonpositive bisectional curvature. We show that a finite cover is biholomorphic and isometric to a flat torus bundle over a compact K\"ahler manifold $N^k$ with $c_1 < 0$. This confirms a…

Differential Geometry · Mathematics 2014-04-30 Gang Liu

We classify non-polar irreducible representations of connected compact Lie groups whose orbit space is isometric to that of a representation of a finite extension of $Sp(1)^k$ for some $k>0$. It follows that they are obtained from isotropy…

Differential Geometry · Mathematics 2017-02-27 Claudio Gorodski , Francisco J. Gozzi

For compact K\"ahlerian manifolds, the holomorphic pseudosymmetry reduces to the local symmetry if additionally the scalar curvature is constant and the structure function is non-negative. Similarly, the holomorphic Ricci-pseudosymmetry…

Differential Geometry · Mathematics 2010-11-18 Zbigniew Olszak

HyperK\"ahler spaces, including manifolds, orbifolds and conical singularities play an important role in superstring/$M$-theory and gauge theories as well as in differential and algebraic geometry. In this paper we provide hundreds of new…

High Energy Physics - Theory · Physics 2025-01-08 Daniel Andrew Baldwin , Bobby Samir Acharya

Nonvanishing theorems play a central role in birational geometry, since they derive geometric consequences from numerical information and constitute a crucial step towards abundance and semiampleness problems. General nonvanishing…

Algebraic Geometry · Mathematics 2025-10-22 Andreas Höring , Vladimir Lazić , Christian Lehn

For a strongly pseudo-convex complex Finsler manifold M, a bundle U of adapted unitary frames is canonically defined. A non-linear Hermitian connection on U, invariant under local biholomorphic isometries, is given and it proved to be…

Differential Geometry · Mathematics 2007-05-23 Andrea Spiro

We consider actions of non-compact simple Lie groups preserving an analytic rigid geometric structure of algebraic type on a compact manifold. The structure is not assumed to be unimodular, so an invariant measure may not exist. Ergodic…

Dynamical Systems · Mathematics 2009-01-06 Amos Nevo , Robert J. Zimmer

A systematic study of the contributions at infinity for the cohomology of variations of polarized Hodge structures over quasicompact K\"ahler manifolds. Several isomorphisms between different cohomologies given.

Algebraic Geometry · Mathematics 2007-05-23 Juergen Jost , Yihu Yang , Kang Zuo